An ovErwhElming riChnEss oF vEgEtAtion mAy hAvE CAusED thE lEvEl oF oxygEn, to risE ABovE toDAy’s ______ , with A CorrEsponDing DEplEtion oF CArBon DioxiDE.
A、ConCEntrAtion B．sAturAtion
C、sAtiAtion
D、plEnituDE